b634477481
This patch extends the generated grub.cfg so that it can use the external environment block when the variable env_block is defined. During boot, if env_block is set, grub.cfg builds a device path for it, exports the variable, and then loads its contents in addition to the normal grubenv file. When GRUB writes variables such as next_entry or saved_entry, the save commands are changed to write into env_block if it is set, and to fall back to the grubenv file otherwise. In this way the external environment block is used automatically, and existing commands like savedefault or save_env do not need to change. Signed-off-by: Michael Chang <mchang@suse.com> Reviewed-by: Neal Gompa <ngompa13@gmail.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This is GRUB 2, the second version of the GRand Unified Bootloader. GRUB 2 is rewritten from scratch to make GNU GRUB cleaner, safer, more robust, more powerful, and more portable. See the file NEWS for a description of recent changes to GRUB 2. See the file INSTALL for instructions on how to build and install the GRUB 2 data and program files. See the file MAINTAINERS for information about the GRUB maintainers, etc. If you found a security vulnerability in the GRUB please check the SECURITY file to get more information how to properly report this kind of bugs to the maintainers. Please visit the official web page of GRUB 2, for more information. The URL is <http://www.gnu.org/software/grub/grub.html>. More extensive documentation is available in the Info manual, accessible using 'info grub' after building and installing GRUB 2. There are a number of important user-visible differences from the first version of GRUB, now known as GRUB Legacy. For a summary, please see: info grub Introduction 'Changes from GRUB Legacy'